mysql - Edit form load. Error: "There is no row at position 0." [VB.net] -


im having problem on thesis. keeps showing message "there no row @ position 0.". though there data in mysql database. please help, i'm newbie. thanks!

private sub frmaccountedit_load(sender object, e eventargs) handles mybase.load         txtuserid.text = frmaccountlist.accountcaller         da = new mysqldataadapter("select * tbl_account userid = '" & txtuserid.text & "'", con)         ds.reset()         da.fill(ds)          try                 cmbacctype.selectedindex = ds.tables(0).rows(0)(1).tostring                 txtusername.text = ds.tables(0).rows(0)(2).tostring                 txtpassword.text = ds.tables(0).rows(0)(3).tostring                 txtfirst.text = ds.tables(0).rows(0)(4).tostring                 txtlast.text = ds.tables(0).rows(0)(5).tostring         catch ex exception             messagebox.show(ex.message, "error!", messageboxbuttons.ok, messageboxicon.error)         end try end sub

run mysql workbench , try query in there work. have more informations query. if there no row 0 query returns nothing. for row count before trying access position 0.

i included class used time. don't want hard code query textboxes that. attacked sql injection. use thing 

sqlquery = "select * tbl_account userid=@coluid"

then use addparam function class add textboxes

dim xdb new mysql xdb.addparam("@coluid", txtuserid.text) xdb.execquery(sqlquery) if xdb.rows.count>0 'you have record  imports mysql.data.mysqlclient  public class mysql      'connection string mysql     public sqlsource string = "server=1.1.1.1;userid=xuser;password=xpassword;"      'database connection classes      private dbcon new mysqlconnection     private sqlcmd mysqlcommand     public dbda new mysqldataadapter     public dbdt new datatable     ' parameters     public params new list(of mysqlparameter)      ' stats     public recordcount integer     public exception string     sub execquery(sqlquery string)          dbcon.connectionstring = sqlsource         try             dbcon.open()             sqlcmd = new mysqlcommand(sqlquery, dbcon)             'loads params query             params.foreach(sub(p) sqlcmd.parameters.addwithvalue(p.parametername, p.value))              'or             'for each p mysqlparameter in params             ' sqlcmd.parameters.addwithvalue(p.parametername, p.value)             ' next             ' clears params              params.clear()             dbda.selectcommand = sqlcmd             dbda.update(dbdt)             dbda.fill(dbdt)             dbcon.close()         catch ex mysqlexception             exception = ex.message                     dbcon.dispose()         end try     end sub     ' add parameters list     public sub addparam(name string, value object)         dim newparam new mysqlparameter(name, value)         params.add(newparam)     end sub end class

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